Work vehicle

ABSTRACT

The present describes a work vehicle where an operator can, on the work vehicle side, confirm which working machine is engaged and set which working machine to engage. A tractor, to which a working machine can be mounted, is provided with: a liquid crystal panel selectably displaying an engageable working machine mounted and displaying the currently engaged working machine so as to be identifiable; an operation unit (encoder dial, enter button, and command buttons) for carrying out selection and determination operations for the working machine displayed on the liquid crystal panel; and a control device that, when a determination operation is carried out by the operation unit for a desired working machine, disengages the currently engaged working machine, and configures the working machine for which the determination operation has been carried out to be engaged.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/518,980 filed Apr. 13, 2017, which is the US national stage ofapplication No. PCT/JP2015/078889 filed Oct. 13, 2015. Priority under 35U.S.C. § 119(a) and 35 U.S.C. § 365(b) is claimed from JP ApplicationNo. 2014-212134 filed Oct. 16, 2014, and JP Application No. 2015-106873filed May 26, 2015; the disclosures of which are incorporated herein byreference.

DESCRIPTION Technical Field

The present invention relates to a work vehicle

Background Art

Conventionally known work vehicles include a tractor for farm work and awheel loader for construction work. Some of such work vehicles use aworking machine attached thereto, corresponding to the work to beperformed. Some working machines can be interlocked with the workvehicles. For example, the tractor can be interlocked with a loader, asprayer, a broadcaster, and the like (refer to Patent Literature 1).

Generally, a working machine is provided with an interlock switch withwhich interlocking with the tractor is turned ON and OFF, and a displaylamp indicating the interlocking with the tractor. Thus, theinterlocking state with respect to the tractor is operated anddisplayed.

CITATION LIST

PTL 1: Japanese Unexamined Patent Application Publication No.2004-329067.

The tractor has no unit for operating and displaying the interlockingstate with respect to the working machine. Thus, the operator on thetractor needs to get off the tractor and move to the working machine tocheck and operate the interlocking state. In particular, when workingmachines, such as a loader and a broadcaster, are attached to front andrear sides of the working machine at the same time, the operator needsto go through a cumbersome procedure of moving to and checking bothworking machines.

An object of the present invention is to provide a work vehicle thatenables an operator to check a currently interlocked working machine andset a working machine to be interlocked on the work vehicle side.

SUMMARY OF THE INVENTION

The present invention provides a work vehicle to which a working machineis attachable, the work vehicle including: a display unit configured todisplay, in a selectable manner, a working machine that is attached andis able to be interlocked, and to display, in an identifiable manner, acurrently interlocked working machine; an operation unit with which anoperation of selecting and determining a working machine displayed, onthe display unit, is performed; and a control unit configured to performcontrol, when an operation of determining a desired working machine isperformed with the operation unit, interlocking of the currentlyinterlocked working machine is released and the desired working machinedetermined by the operation is interlocked.

In the above-described work vehicle, the display unit may be configuredto display a working machine that is not attached and is able to beinterlocked, in an identifiable and non-selectable manner.

In the above-described work vehicle, the control unit may be configuredto perform control in such a manner that the working machine that isattached and is able to be interlocked is detected at a predeterminedinterval.

In the above-described work vehicle, the operation unit may include aplurality of buttons and an encoder dial integrally provided to thedisplay unit.

The above-described work vehicle may further include a transmissionlever connected to the control unit; and a switch provided to thetransmission lever. When a sprayer is interlocked as the workingmachine, the switch may be assigned with any one of a spraying start/endfunction for the sprayer, a spraying amount adjustment function for thesprayer, an extending/contracting adjustment function for a boom of thesprayer, an inclination adjustment function for the boom, anopening/closing adjustment function for the boom, and a lifting/loweringadjustment function for the boom.

The above-described work vehicle may further include a transmissionlever connected to the control unit; and a switch provided to thetransmission lever. When a broadcaster is interlocked as the workingmachine, the switch may be assigned with a spraying start/end functionfor the broadcaster or a spraying amount adjustment function for thebroadcaster.

With the work vehicle according to the present invention, a unit foroperating and displaying an interlocking state with the working machineis provided on a work vehicle side. Thus, the operator can set and checkthe interlocking state of the working machine on the side of the workvehicle. Thus, the operator on the work vehicle can check the currentlyinterlocked working machine and set the working machine to beinterlocked, while being on the work vehicle, that is, without gettingoff the work vehicle and moving to the working machine, and thus canenjoy a higher work efficiency.

A unit for operating and displaying the interlocking state with respectto the work vehicle can be omitted from the working machine, and thus acost reduction can be achieved. When the unit for operating anddisplaying the interlocking state with respect to the work vehicle isprovided to the working machine, the operator can set and check theinterlocking state on the work vehicle and on the working machine andthus can enjoy a higher operability.

With the work vehicle according to the present invention, a workingmachine that can be interlocked but is not attached may be displayed inthe identifiable manner. Thus, the operator can enjoy higher conveniencewith the working machine that can be interlocked but is not attachedbeing immediately identifiable. The working machine that can beinterlocked but is not attached cannot be selected, and thus isprevented from being accidentally selected by the operator.

With the work vehicle according to the present invention, the workingmachine that is attached and can be interlocked is detected at apredetermined interval. Thus, a latest state indicating a workingmachine that can be interlocked can be displayed.

With the work vehicle according to the present invention, the pluralityof buttons and the encoder dial integrally formed with the display unitmay be used as the operation unit. Thus, an operation can be intuitivelyand quickly performed.

With the work vehicle according to the present invention, the switchprovided to the transmission lever may be assigned with the desiredfunction for operating the interlocked working machine. Thus, theoperator can easily operate the assigned functions at hand withoutreleasing his or her hand from the transmission lever and thus can enjoya less cumbersome operation. All things considered, higher operabilityand work efficiency can be achieved, and a load on the operator can bereduced.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an external perspective view of a tractor.

FIG. 2 is a diagram viewed in the direction of an arrow X in FIG. 1 .

FIG. 3 is a diagram viewed in the direction of an arrow Y in FIG. 1 .

FIG. 4 is a diagram viewed in the direction of an arrow Z in FIG. 1 .

FIG. 5 is a diagram illustrating a power transmission system of thetractor.

FIG. 6 is a diagram illustrating a link mechanism of the tractor.

FIG. 7 is a diagram illustrating an operator's seat of the tractor andits periphery.

FIG. 8 is a diagram illustrating a field of view of an operator.

FIG. 9 is a diagram illustrating an information network of the tractor.

FIG. 10 is a diagram illustrating a display.

FIG. 11 is a diagram illustrating a portion of a control system of thetractor related to the display.

FIG. 12 is a diagram illustrating a screen displayed on the display.

FIG. 13 is a diagram illustrating a screen displayed on the display.

FIG. 14 is a diagram illustrating a screen displayed on the display.

FIG. 15 is a diagram illustrating a screen displayed on the display.

FIG. 16 is a diagram illustrating a screen displayed on the display.

FIG. 17 is a diagram illustrating an operation control tool provided toan armrest.

FIG. 18 is a diagram illustrating an example of a CAN.

FIG. 19 is a diagram schematically illustrating the CAN connectionbetween the tractor and a working machine.

FIG. 20 is a block diagram illustrating a configuration of the CAN inthe tractor.

FIG. 21 is a diagram illustrating a screen displayed on the display.

FIG. 22 is a diagram illustrating an instrument panel.

FIG. 23 is a diagram illustrating a screen displayed on the display.

FIGS. 24A and 24B are schematic views illustrating control in a casewhere a spraying amount of a sprayer is increased, and includes 24Aillustrating constant vehicle speed control, and 24B illustratingconstant spraying pressure control.

FIG. 25 is a diagram illustrating a screen displayed on the display.

FIG. 26 is a diagram illustrating a screen displayed on the display.

EMBODIMENTS OF THE INVENTION

The technical concept of the present invention is applicable to any workvehicle. The following gives a description using a tractor, which is atypical work vehicle, as an example.

First, a tractor 1 is briefly described.

FIG. 1 illustrates the tractor 1. FIG. 2 is a diagram viewed in thedirection of an arrow X in FIG. 1 , FIG. 3 is a diagram viewed in thedirection of an arrow Y in FIG. 1 , and FIG. 4 is a diagram viewed inthe direction of an arrow Z in FIG. 1 . In these figures, the front andrear direction, the right and left direction, and the upper and lowerdirection of the tractor 1 are illustrated.

The tractor 1 mainly includes a frame 11, an engine 12, a transmission13, a front axle 14, and a rear axle 15. The tractor 1 further includesa cabin 16. The cabin 16 has an inner side serving as an operationcontrol room in which an operator's seat 161, an accelerator pedal 162,a shift lever 163, and the like are arranged (see FIG. 7 ).

The frame 11 serves as a front frame of the tractor 1. The frame 11, thetransmission 13, and the rear axle 15 form a chassis of the tractor 1.The frame 11 is provided with a pair of working machine supporters 32that supports a working machine (for example, a loader) attached to afront portion of the tractor 1.

The working machine supporters 32 are formed of plate shaped membersprotruding outward and extending upward from left and right sidesurfaces of the frame 11. The working machine supporters 32 have upperportions provided with a hole and a notch with which the working machineis attached.

The engine 12 is supported by the frame 11. The engine 12 burns fuel,and converts thermal energy thus obtained into kinetic energy. Thus, theengine 12 burns fuel to generate rotary driving force. An enginecontroller (not illustrated) is connected to the engine 12. When anoperator operates the accelerator pedal 162 (see FIG. 7 ), the enginecontroller changes an operational state of the engine 12 in accordancewith the operation. The engine 12 is provided with an exhaust gaspurifier 12E. The exhaust gas purifier 12E oxidizes fine particles,carbon monoxide, hydrocarbon, and the like in exhaust gas.

The transmission 13 transmits the rotary driving force from the engine12 to the front axle 14 and the rear axle 15. The transmission 13receives the rotary driving force from the engine 12 via a connectionmechanism. The transmission 13 is provided with a continuously variabletransmission (I-HMT) 131 (see FIG. 5 ). When the operator operates theshift lever 163 (see FIG. 7 ), the continuously variable transmission131 changes an operating state of the transmission 13 in accordance withthe operation.

The front axle 14 transmits the rotary driving force from the engine 12to front wheels 141. The front axle 14 receives the rotary driving forcefrom the engine 12 via the transmission 13. A steering device (notillustrated) is arranged adjacent to the front axle 14. When theoperator operates a steering wheel 164 (see FIG. 7 ), the steeringdevice changes a steering angle of the front wheels 141 in accordancewith the operation.

The front axle 14 is provided with a hydraulic pump 142 (see FIG. 5 ).When the operator operates a joystick 176 (see FIG. 7 ), the hydraulicpump 142 transmits hydraulic pressure to the working machine attached tothe front portion of the tractor 1 in accordance with the operation.

The rear axle 15 transmits the rotary driving force from the engine 12to rear wheels 151. The rear axle 15 receives the rotary driving forcefrom the engine 12 via the transmission 13. The rear axle 15 is providedwith a PTO output device 152 (see FIG. 5 ). When the operator operates aPTO switch 165 (see FIG. 7 ), the PTO output device 152 transmits therotary driving force to a working machine being pulled, in accordancewith the operation. The rear axle 15 is also provided with a linkmechanism 35 (see FIG. 6 ). [0057] Next, a power transmission system ofthe tractor 1 is described. [0058] FIG. 5 illustrates the powertransmission system of the tractor 1. It is to be noted that each figuresimply illustrates only portions required for the description of thepresent invention.

As described above, the transmission 13 transmits rotary driving forcefrom the engine 12 to the front axle 14 and the rear axle 15. Thus, thetransmission 13 has a mechanism for transmitting the rotary drivingforce to the front axle 14 and a mechanism for transmitting the rotarydriving force to the rear axle 15. In this description, the mechanismfor transmitting the rotary driving force to the front axle 14 isreferred to as a front drive mechanism 33.

The front drive mechanism 33 includes a drive shaft 331, aconstant-speed drive gear 332, and an acceleration drive gear 333. Thefront drive mechanism 33 further includes a constant speed clutch 334, aconstant speed driven gear 335, an acceleration clutch 336, and anacceleration driven gear 337. The front drive mechanism 33 furtherincludes an output shaft 338.

The drive shaft 331 is rotatably supported via a bearing. Theconstant-speed drive gear 332 is attached to the drive shaft 331. Theacceleration drive gear 333 is also attached to the drive shaft 331.Thus, the constant-speed drive gear 332 and the acceleration drive gear333 [0062]

The constant speed clutch 334 is rotatably supported via a bearing. Theconstant speed driven gear 335 is attached to an inner hub of theconstant speed clutch 334 while meshing with the constant-speed drivegear 332. Thus, the constant speed driven gear 335 rotates while beingintegrated with the inner hub of the constant speed clutch 334. Theacceleration clutch 336 is also rotatably supported via a bearing. Theacceleration driven gear 337 is attached to an inner hub of theacceleration clutch 336 while meshing with the acceleration drive gear333. Thus, the acceleration driven gear 337 rotates while beingintegrated with the inner hub of the acceleration clutch 336.

The output shaft 338 is rotatably supported via a bearing. The constantspeed clutch 334 has an outer cylinder attached to the output shaft 338.Thus, the outer cylinder of the constant speed clutch 334 rotates whilebeing integrated with the output shaft 338. The acceleration clutch 336also has an outer cylinder attached to the output shaft 338. Thus, theouter cylinder of the acceleration clutch 336 rotates while beingintegrated with the output shaft 338.

With this structure, when the inner hub of the constant speed clutch 334is coupled to the outer cylinder (when the constant speed clutch 334operates), the rotation of the drive shaft 331 is transmitted to theoutput shaft 338. Then, a propeller shaft 43 rotates, and thus the frontwheels 141 rotate via a differential mechanism 34. When the four-wheeldrive is achieved with the constant speed clutch 334 operated, the rearwheels 151 and the front wheels 141 rotate at the same circumferentialspeed (referred to as constant speed four-wheel drive).

Similarly, also when the inner hub of the acceleration clutch 336 iscoupled to the outer cylinder (when the acceleration clutch 336operates), the rotation of the drive shaft 331 is transmitted to theoutput shaft 338. Then, the propeller shaft 43 rotates, and thus thefront wheels 141 rotate via the differential mechanism 34. When thefour-wheel drive is achieved with the acceleration clutch 336 operated,the front wheels 141 rotate with a higher circumferential speed thanthat of the rear wheels 151 (referred to as acceleration four-wheeldrive).

Next, the link mechanism 35 of the tractor 1 is described.

FIG. 6 illustrates the link mechanism 35 of the tractor 1. The linkmechanism 35 includes: a top bracket 351 attached to a rear portion ofthe rear axle 15; and a top link 352 attached to a hinge portion of thetop bracket 351. The link mechanism 35 further includes: a lower bracket353 attached to a lower portion of the rear axle 15; and a lower link354 attached to a hinge portion of the lower bracket 353.

The link mechanism 35 further includes: lift arms 355 attached to sideportions of the rear axle 15; a lifting and lowering actuator 356attached to a center portion of the lift arm 355; a lift link 357attached to the left lift arm 355 and the lower link 354; and aninclination actuator 358 attached to the right lift arm 355 and thelower link 354.

With the link mechanism 35 having this configuration, the workingmachine attached to the tractor 1 can be lifted, lowered, and inclinedwith three links including the top link 352 and the two lower links 354.

Next, the operation control room of the tractor 1 is described.

FIG. 7 illustrates the operator's seat 161 and its periphery. FIG. 8illustrates a field of view of the operator. FIG. 17 illustrates anoperation control tool provided to an armrest 161 r.

As described above, the cabin 16 has the inner side serving as theoperation control room in which the operator's seat 161, the acceleratorpedal 162, the shift lever 163, and the like are arranged. A brake pedal166, a clutch pedal 167, a reverser lever 168, a speed dial 169, aninstrument panel 170, a control panel 171, a transmission lever 172, aworking machine lifting/lowering switch 173, working machinelifting/lowering fine-control switches 174, and the like are arranged inthe periphery of the operator's seat 161. The operator can operate theaccelerator pedal 162, the shift lever 163, and the like while beingseated on the operator's seat 161 to operate the tractor 1.

The control panel 171 is disposed in the armrest 161 r that can beopened and closed, and is connected to the control device 3. The controlpanel 171 is an operation tool for performing various settings relatedto the working machine. The operator can perform various settingssuitable for the connected working machine, by operating the controlpanel 171.

The transmission lever 172 is disposed on an upper surface of the frontportion of the armrest 161 r, and is connected to the control device 3.When the operator inclines the transmission lever 172 having a pivotablestructure as appropriate, a shifting operation is performed. Thus, theoperator can freely adjust the traveling speed.

The working machine lifting/lowering switch 173 is provided on the frontsurface of the transmission lever 172 (see FIG. 17 ). The workingmachine lifting/lowering switch 173 is a slidable switch for lifting andlowering the working machine attached to the rear portion of the tractor1. The working machine lifting/lowering switch 173 is connected to thecontrol device 3. When the working machine lifting/lowering switch 173is slid upward, the working machine is lifted. When the working machinelifting/lowering switch 173 is slid downward, the working machine islowered. Thus, the operator can freely lift and lower the workingmachine attached to the rear portion of the tractor 1.

A pair of upper and lower working machine lifting/lowering fine-controlswitches 174 are provided on a left surface of the transmission lever172 (see FIG. 17 ). The working machine lifting/lowering switches 174are push switches for lifting and lowering the working machine attachedto a rear portion of the tractor 1, within a small range. The workingmachine lifting/lowering fine-control switches 174 are connected to thecontrol device 3. The working machine is lifted within a small rangewhen the upper switch is pressed, and is lowered in a small range whenthe lower switch is pressed. Thus, the operator can freely lift andlower the working machine attached to the rear portion of the tractor 1.Thus, the operator can roughly adjust the height of the working machinewith the working machine lifting/lowering switch 173 and then finelyadjust the height with the working machine lifting/lowering fine-controlswitches 174.

The joystick 176 is disposed on the right side of the operator's seat161 (see FIG. 7 ). The operator can operate the working machine (forexample, a loader) attached to the front portion of the tractor 1, byoperating the joystick 176 while being seated on the operator's seat161.

The tractor 1 includes a display 2 disposed close to the operator's seat161. The display 2 is disposed on a front right side of the operator'sseat 161 so as to be operable with the right hand of the operator. Aninformation network of the tractor 1 is briefly described below.Furthermore, the display 2 and a control system including the display 2are described in detail below.

FIG. 9 illustrates the information network of the tractor 1. FIG. 10illustrates the display 2. FIG. 11 illustrates a portion of the controlsystem of the tractor 1 related to the display 2. The control device 3includes a storage unit 31, and can store information required for thecontrol. The storage unit 31 may be provided outside the control device3.

The tractor 1 has the information network installed over variouslocations to achieve the maximum performance. Specifically, thetransmission 13, the instrument panel 170, the control panel 171, andthe display 2 form a controller area network (CAN) together with theengine 12 so that the components can share information with each other.

As illustrated in FIG. 18 , the CAN may include the working machine.Examples of information communicated between the tractor 1 and workingmachines A to C include: rotation speed and water temperature of theengine 12; vehicle speed; a transmission stage; a state of thetransmission 13; and a state of the link mechanism 35 (depth,inclination, or the like). The engine 12, the transmission 13, and thelink mechanism 35 are collectively controlled by the control device 3,and information on these and warning are displayed on the instrumentpanel 170 or the display 2. Sophisticated control can be achieved withthese various pieces of information transmitted between the tractor 1and the working machines A to C. Thus, higher operability and workefficiency can be achieved, and a load on the operator can be reduced.

FIG. 19 is a diagram schematically illustrating the CAN connectionbetween the tractor 1 and the working machine. As illustrated in FIG. 19, the control device 3 serving as the tractor side controller isprovided to the tractor 1, and a working machine side controller 5 forcontrolling the working machine is provided to the working machine. Thetractor side controller and the working machine side controller 5 areconnected to each other via a connector 6. The connector 6 may be aconnector of the AG-PORT standard or the ISOBUS standard. Thus,bidirectional communications may be performed between the tractor sidecontroller and the working machine side controller 5. Thus, for example,the lever and the like on the side of the tractor 1 can be assigned theoperation of the working machine, and thus more consistent operabilitycan be achieved. Furthermore, the cabin 16 can incorporate less wiring.

FIG. 20 is a block diagram illustrating a configuration of the CAN inthe tractor 1. An example where a loader, a sprayer, and a broadcasterserving as working machines can be connected to the CAN of the tractor 1is described with reference to FIG. 20 . The display 2, the connector 6,the engine 12, the transmission 13, the instrument panel 170, thecontrol panel 171, the transmission lever 172, the working machinelifting/lowering switch 173, the working machine lifting/loweringfine-control switches 174, a loader operation panel 175, a CAN interface177, and a broadcaster controller 181 are connected to the controldevice 3 serving as the tractor side controller via the CAN. Thejoystick 176 is connected to the loader operation panel 175. A sprayeroperation panel 178, a spraying controller 179, and a boom operationcontroller 180 are connected to the CAN interface 177.

The loader operation panel 175 is a dedicated operation tool for settingup the loader. The operator can perform various setting related to theloader by operating the loader operation panel 175. Thus, the controldevice 3 can acquire the information related to the content set with theloader operation panel 175. The operator can operate the loader inaccordance with various settings, by operating the joystick 176.

The CAN interface 177 is an interface for connecting the sprayeroperation panel 178, the spraying controller 179, and the boom operationcontroller 180 to the control device 3 via the CAN.

The sprayer operation panel 178 is a dedicated operation tool forsetting up the sprayer. The operator can perform various settings (suchas a setting on the amount of pesticide sprayed per unit area) relatedto the sprayer by operating the sprayer operation panel 178. Thus, thecontrol device 3 can acquire information related to the content set withthe sprayer operation panel 178.

The spraying controller 179 is used for performing opening/closingoperation for spray valves through which pesticides are supplied tospray nozzles. The control device 3 acquires the information related tothe state of the spray valves set with the spraying controller 179, andcontrols the spray valves. Thus, the operator can adjust the sprayingstart/end timing and the spraying amount of the pesticides by operatingthe spraying controller 179.

The boom operation controller 180 is operated for adjusting theextending/contracting, inclination, opening/closing, andlifting/lowering of a boom. The control device 3 acquires information onthe state of the boom set with the boom operation controller 180, andcontrols the boom. Thus, the operator can adjust theextending/contracting, inclination, opening/closing, andlifting/lowering of the boom by operating the boom operation controller180.

The broadcaster controller 181 is operated for adjusting the sprayingstart/end timing and the spraying amount of the broadcaster. The controldevice 3 acquires information related to the state of the broadcasterset by the broadcaster controller 181, and controls the broadcaster.Thus, the operator can adjust the spraying start/end timing and thespraying amount of the broadcaster by operating the broadcastercontroller 181.

In the tractor 1, the display 2 is disposed on a side console (see FIGS.7 and 8 ). The display 2 includes a liquid crystal panel (display unit)21, an encoder dial (operation unit) 22, an enter button (operationunit) 23, and five command buttons (operation unit) 24 to 28 integrallyprovided (see FIG. 10 ).

The liquid crystal panel 21 is provided at the center of the frontsurface of the display 2. The liquid crystal panel 21 can display apredetermined screen based on an instruction from the control device(control unit) 3. For example, the liquid crystal panel 21 can displayan opening screen S1 (see FIG. 12 ) based on an instruction from thecontrol device 3. The liquid crystal panel 21 can display other screens(see FIG. 13 to FIG. 16 ) based on instructions from the control device3. The display unit is not limited to the liquid crystal panel 21, andmay be a thin display panel such as an electroluminescence (EL) panelusing organic EL or inorganic EL.

The encoder dial 22 is provided on an upper right side of the display 2.The encoder dial 22 incorporates a rotary encoder, and can transmit anintension of the operator (selection operation), to scroll a tab orshift a highlighted display, to the control device 3 for selecting anelement (item) displayed on the liquid crystal panel 21. For example,the encoder dial 22 can transmit an intension of the operator forscrolling a tab for selecting among displayed numbers and alphabets, tothe control device 3 (see FIG. 13 ). The encoder dial 22 can transmit anintension of the operator to shift a highlighted display, for selectinga displayed icon, to the control device 3 (see FIG. 14 to FIG. 16 ).

The enter button 23 is integrally formed with the encoder dial 22. Theenter button 23 is an operation button corresponding to the upper andlower movement of the encoder dial 22, and is operated by pressing theupper surface of the encoder dial 22. The enter button 23 may be a pushbutton provided on an upper end surface of the encoder dial 22.

The enter button 23 can transmit an intension of the operator(determination operation) to determine one of the elements (items)displayed on the liquid crystal panel 21 to the control device 3. Forexample, the enter button 23 can transmit an intension of the operatorto determine one of the displayed numbers or alphabets, to the controldevice 3 (see FIG. 13 ). The enter button 23 can transmit an intensionof the operator to determine one of the displayed icons, to the controldevice 3 (see FIG. 14 to FIG. 16 ).

The five command buttons 24 to 28 are operation buttons for performingan operation for determining an icon displayed in the upper end of thescreen. The command buttons 24 to 28 are arranged side by side in theupper portion of the front surface of the display 2. The command buttons24 to 28 each correspond to an icon immediately therebelow on the liquidcrystal panel 21. The command buttons 24 to 28 can each transmit anintension of the operator to determine a corresponding one of the iconsto the control device 3. When any one of the command buttons 24 to 28 ispressed, the control device 3 executes a command related to thecorresponding icon. The icon and command assigned to each of the commandbuttons 24 to 28 differ among the screens. Thus, required icons andcommands are assigned to each screen.

The commands include: a command (corresponding icon is “HOME”) forinstructing switching to a first home screen S3, a command(corresponding icon is “free 1” or “free 2”) for instructing switchingto a shortcut screen (a screen freely set by the operator), a command(corresponding icon is “determine”), with a similar function as theenter button 23, for instructing determination of an element, a command(corresponding icon is “return”) for instructing switching to a previousscreen, and a command (corresponding icon is an arrow indicating acertain direction) for instructing a direction in which a tab isscrolled and a direction in which the highlighted display is shifted.

The liquid crystal panel 21 may be provided with a touch panel as theoperation unit. In this configuration, the encoder dial 22, the enterbutton 23, and the command buttons 24 to 28 can be omitted asappropriate.

Some working machines can be interlocked with the tractor 1. When theworking machine that can be interlocked is attached to the tractor 1,the tractor 1 and the working machine can operate in an interlockingmanner. The interlocking manner means that the tractor 1 operates in anoptimum manner in accordance with an operation of the working machine.The interlocking manner may also mean that the working machine operatesin an optimum manner in accordance with an operation of the tractor 1.The working machine that can be interlocked with the tractor 1 includesa loader attached to the front portion, as well as a sprayer and abroadcaster attached to the rear potion, and the like.

For example, when the loader is attached to the tractor 1 in theinterlocking manner, the tractor 1 is automatically controlled under asetting optimum for the loader. As a specific example, control may beperformed in such a manner that the acceleration four-wheel drive isautomatically switched to the constant speed four-wheel drive for safetypurposes. In a case where the loader is expected to be lifted, such as acase where the loader has been detected to be knocked down, control isperformed in such a manner that the engine rotation speed increases,whereby the loader can be lifted at a higher speed.

In this context, the storage unit 31 stores a list of working machinesthat can be interlocked. The control device 3 reads the list of workingmachines that can be interlocked from the storage unit 31, generates aninterlocking working machine screen S5 (see FIG. 16 ), and performscontrol in such a manner that the liquid crystal panel 21 displays thescreen. Specifically, the interlocking working machine is added as onemenu to the screen (see, for example, a second home screen S4), on whicha plurality of menus are displayed in a selectable manner. When anoperation of selecting and determining the interlocking working machineis performed, the interlocking working machine screen S5 can bedisplayed. The interlocking working machine screen S5 displays theattached interlocking working machines in a selectable manner, and theinterlocking working machines in an identifiable manner.

The selectable manner means that the display can be in any format aslong as the operator can select the desired working machine. Forexample, the desired working machine may be selectable through shiftingthe highlighted display by operating the operation unit (encoder dial22, enter button 23, command buttons 24 to 28). The identifiable mannermeans that the display can be in any format as long as the operator canidentify the currently interlocked working machine. For example, theidentifiable manner can be achieved with a mark (such as ON display),indicating that the machine is currently interlocked, displayed on theicon of the working machine that is currently interlocked in anoverlapping manner, and with a mark (such as OFF display), indicatingthat the machine is not currently interlocked, displayed on the icon ofthe working machine that is currently not interlocked in an overlappingmanner.

The working machine that can be interlocked but is not attached isdisplayed in an identifiable and non-selectable manner. For example, theicon may be grayed out so as to be identifiable as a working machinethat is not attached, and controlled in such a manner as not to beselectable by operating the operation unit. Thus, the operator can enjoyhigher convenience with the working machine that can be interlocked butis not attached being immediately identifiable. The working machine thatis not attached cannot be selected, and thus is prevented from beingaccidentally selected by the operator.

The control device 3 receives selection using the operation unit(encoder dial 22, enter button 23, command buttons 24 to 28) and thedetermination operation on the interlocking working machine screen S5,and performs control such that the working machine determined throughthe operation is stored in the storage unit 31.

When a desired working machine is determined through an operation on theinterlocking working machine screen S5, the control device 3 performscontrol in such a manner that the working machine determined by theoperation is interlocked with the interlocking of the interlockedworking machine released. Thus, even when the working machines areattached to the front and rear of the tractor 1, only one workingmachine is interlocked at a time, whereby the control on the tractor 1is prevented from being hindered.

The control device 3 performs control in such a manner that the workingmachine that is attached and can be interlocked is detected at apredetermined interval (for example, once in every 10 minutes, or whenthe operation of determining the interlocking working machine isperformed on the second home screen S4). Whether a working machine canbe interlocked can be determined in accordance with communications withthe working machine. Thus, the interlocking working machine screen S5can always display the latest state.

With the display 2 on which the interlocking state of the workingmachine with respect to the working machine is operated and displayedthus provided to the tractor 1, the operator can set and check theinterlocking state of the working machine on the side of the tractor 1.Thus, the operator on the tractor 1 can check the currently interlockedworking machine and set the working machine to be interlocked, whilebeing on the tractor 1, that is, without getting off the tractor 1 andmoving to the working machine, and thus can enjoy a higher workefficiency.

Furthermore, the unit for operating and displaying the interlockingstate with respect to the tractor 1 can be omitted from the workingmachine, and thus a cost reduction can be achieved. When the unit foroperating and displaying the interlocking state with respect to thetractor 1 is provided to the working machine, the operator can set andcheck the interlocking state on the tractor 1 and on the working machineand thus can enjoy a higher operability.

A screen displayed on the display 2, related to the interlocking betweenthe tractor 1 and the working machine, and how the display 2 is operatedare described below.

FIG. 12 to FIG. 16 illustrate a screen displayed on the display 2. It isto be noted that each figure simply illustrates only portions requiredfor the description of the present embodiment.

First of all, an opening screen S1 is displayed on the display 2 (seeFIG. 12 ). In the opening screen S1, a symbol mark Sm is displayed at aportion around the center. The symbol mark Sm is a design representing asupplier/manufacturer. The symbol mark Sm appears on a black backgroundimage, and gives a strong impression to the operator.

Next, the display 2 displays an unlock screen S2 (see FIG. 13 ). Theunlock screen S2 display four scroll boxes Sb1 to Sb4 for inputting asingle row of PIN code. A selected one of the scroll boxes Sb1 to Sb4 isdisplayed in a highlighted manner (see a section H in the figure). Inthe scroll boxes Sb1 to Sb4, any one of the numbers 0 to 9 and alphabetsA to F can be selected through vertical scrolling.

The unlock screen S2 displays icons 251, 261, 271, 281 corresponding tothe command buttons 25 to 28 at the upper end. The unlock screen S2displays a dialog box Db1 in which an operator name is displayed, and adialog box Db2 in which a working machine name is displayed. Theoperator can check whether the operator name and the working machinename are correctly set with these dialog boxes Db1 and Db2.

The operator can select a number or an alphabet by rotating the encoderdial 22 through scrolling, and determine the number or the alphabet bypressing the enter button 23. In the unlock screen S2, the commandbutton 25 or 26 can be pressed to select between the numbers oralphabets through scrolling, and determine the number or alphabet bypressing the command button 27. The determination may be cancelled bypressing the command button 28. When an incorrect PIN code is input, amessage indicating that the number is incorrect is displayed.

Next, the display 2 displays the first home screen S3 (see FIG. 14 ).The first home screen S3 displays icons Ia1 to Ia10 for selecting a menuor a page. Selected one of the icons Ia1 to Ia10 is displayed in ahighlighted manner (see a section H in the figure). The highlighteddisplay is shifted by rotation of the encoder dial 22. Icons that cannotbe selected are grayed out (see a section G in the figure). The firsthome screen S3 displays icons 242, 252, 262, 272, and 282, correspondingto the command buttons 24 to 28, at the upper end.

How the icon 242 corresponding to “free 1” and the icon 252corresponding to “free 2” are registered is briefly described withregistration for “free 1” as an example. First of all, the commandbutton 24 associated with the icon 242 corresponding to “free 1” is longpressed (for example, for 3 minutes) to cause transition to theregistration screen (not illustrated). Then, the encoder dial 22 isoperated with the registered screen displayed, to select a desired icon(for example, the icon “OFF”) and the enter button 23 is pressed. Thus,this icon is registered to the icon 242 corresponding to “free 1”, andthe icon is displayed instead of “free 1”.

While the first home screen S3 is displayed, the operator can select thedesired one of icons Ta1 to Ia10 by rotating the encoder dial 22, andcan determine the icon by pressing the enter button 23 or the commandbutton 27. Here, the icon Ia10 with a description “next page” isselected and determined.

Next, the display 2 displays the second home screen S4 (see FIG. 15 ).The second home screen S4 displays icons Ib1 to Ib10. The selected oneof the icons Ib1 to Ib10 is displayed in a highlighted manner (see thesection H illustrated in the figure). The highlighted display is shiftedby rotation of the encoder dial 22. The second home screen S4 displaysicons 243, 253, 263, 273, and 283, corresponding to the command buttons24 to 28, at the upper end.

In the second home screen S4, the operator can select the desired one ofthe icons Ib1 to Ib10 by rotating the encoder dial 22, and determine theicon by pressing the enter button 23 or the command button 27. Here, theicon Ib2, with a description “interlocking working machine”, is selectedand determined.

Next, the interlocking working machine screen S5 is displayed on thedisplay 2 (see FIG. 16 ). The interlocking working machine screen S5displays three icons Ic1 to Ic3 with the working machine name and ON orOFF. The interlocking working machine screen S5 displays icons 244, 254,264, 274, and 284, corresponding to the command buttons 24 to 28, at theupper end.

The icons Ic1 to Ic3 are a list of working machines that can beinterlocked. The icons Ic1 and Ic3 indicate the working machines thatcan be interlocked and are attached, and are displayed in a selectablemanner. The icon Ic2 indicates a working machine that can be interlockedbut is not attached, and is displayed in a non-selectable manner. Theicon Ic2 is grayed out meaning that the icon cannot be selected. Theicon Ic2 is not selected through the rotation of the encoder dial 22.

Thus, while the interlocking working machine screen S5 is displayed, theoperator selects the desired icon Ic1 or Ic3 by rotating the encoderdial 22, and can switch between ON and OFF by pressing the enter button23. ON indicates that the machine is interlocked and OFF indicates thatthe machine is not interlocked.

FIG. 16 illustrates a state where the icon Ic2 cannot be selected, andthe determination operation can be performed for the icon Ic1 or Ic3.Specifically, when one of the icons Ic1 and Ic3, corresponding to theinterlocked working machines, is switched from ON to OFF, the workingmachine is no longer interlocked. On the other hand, the working machinecorresponding to the other one of the icons Ic1 and Ic3 determined bythe operation, switched from OFF to ON, is interlocked. Thus, only oneworking machine is interlocked at a time.

FIG. 21 illustrates another example of the interlocking working machinescreen. The icons Id1 to Id3 are a list of working machines that can beinterlocked. This interlocking working machine screen S51 uses ahighlighted display (icon Id1) for displaying the working machine thatcan be interlocked and is attached in a selectable manner. In theinterlocking working machine screen S51, a green point image Id4 isoverlapped on the icon corresponding to the currently interlockedworking machine, so that the currently interlocked working machine canbe identified. On the interlocking working machine screen S51, theworking machine that can be interlocked but is not attached has acorresponding icon (icon Id2) with a gray background indicating that theworking machine cannot be selected in an identifiable manner.

The instrument panel 170 may be provided with an interlocking lamp 170 aindicating the interlocked state, as illustrated in FIG. 22 . Theinterlocking lamp 170 a is turned ON when the tractor 1 and the workingmachine are interlocked, and is turned OFF when they are notinterlocked. Thus, the operator can easily recognize whether the workingmachine is interlocked, simply by looking at the instrument panel 170.

Next, another featured configuration related to the interlocking betweenthe tractor 1 and the working machine is described. In the descriptionbelow, a case where the interlocked working machine is a sprayer and acase where the interlocked working machine is a broadcaster areseparately described.

When the interlocked working machine is a sprayer, the working machinelifting/lowering switch 173 and the working machine lifting/loweringfine-control switches 174 can each be assigned with any one of a sprayerspraying start/stop function, a sprayer spraying amount adjustmentfunction, a sprayer boom extending/contracting function, a boominclination adjustment function, a boom opening/closing adjustmentfunction, and a boom lifting/lowering adjustment function. Theassignment is invalid when the working machine is not interlocked.

A function assigned to each switch can be set by the operator in advanceby using the display 2, for example. When the tractor setting (icon Ia3)is selected and determined on the first home screen S3, various tractorsetting items are displayed, and sprayer switch assignment setting iscalled therefrom. Thus, a switch assignment screen S6 as illustrated inFIG. 23 is displayed.

On the switch assignment screen S6, two icons Ie1 and Ie2 on which namesof switches that can be assigned are displayed, and icons Ie3 and Ie4displayed on the right of the icons Ie1 and Ie2 and on which functionsassigned to the switches Ie1 and Ie2 are described are displayed. Theicons Ie3 and Ie4 are selectively displayed. The switch assignmentscreen S6 displays the icons 244, 254, 264, 274, and 284, correspondingto the command buttons 24 to 28, at the upper end.

While the switch assignment screen S6 is displayed, the operator selectsthe desired icon Ie3 or Ie4 by operating the encoder dial 22, andpresses the enter button 23. Thus, the display content of the selectedicon can be scrolled with the encoder dial 22. Then, the operatorselects a desired function by operating the encoder dial 22, and pressesthe enter button 23. Then, the selected function is assigned to theswitch described on the icon displayed on the left side.

As an example, in FIG. 23 , the sprayer spraying start/stop is assignedto the working machine lifting/lowering switch 173. More specifically,the spraying starts when the working machine lifting/lowering switch 173is slid upward, and stops when the switch is slid downward. The boomlifting/lowering adjustment is assigned to the working machinelifting/lowering fine-control switches 174. More specifically, the boomis lifted when the upper one of the working machine lifting/loweringfine-control switches 174 is pressed, and is lowered when the lower oneof the switches is pressed.

As described above, the desired functions for operating the currentlyinterlocked working machine are assigned to the switches (the workingmachine lifting/lowering switch 173 and the working machinelifting/lowering fine-control switches 174) provided to the transmissionlever 172. Thus, the operator can easily operate the assigned functionsat hand without releasing his or her hand from the transmission lever172 for operating the spraying controller 179 or the boom operationcontroller 180, and thus can enjoy a less cumbersome operation.

When the interlocked working machine is a sprayer, two types of control,including constant vehicle speed control and constant spraying pressurecontrol, can be performed. In the constant vehicle speed control, thevehicle speed is kept constant with the spraying pressure adjusted, whenthe spraying amount is changed. In the constant spraying pressurecontrol, the spraying is performed with a constant spraying pressurewith the vehicle speed adjusted, when the spraying pressure is changed.

FIGS. 24A and 24B area schematic view illustrating both types of controlin a case where the spraying amount is increased, and includes 24Aillustrating the constant vehicle speed control, and 24B illustratingthe constant spraying pressure control. As illustrated in FIG. 24A, inthe constant vehicle speed control, the vehicle speed is automaticallymaintained to be constant and the spraying pressure automatically rises,when the spraying amount per target acreage is increased. As illustratedin FIG. 24B, in the constant spraying pressure control, the vehiclespeed automatically drops and the spraying pressure is automaticallymaintained to be constant, when the spraying amount per target acreageis increased. The constant spraying pressure control involves no changein the particle size and no change in the spraying state even when thespraying amount is changed, and thus can achieve more accurate work.

Which one of the two types of control is performed can be set by theoperator in advance. The control modes can be set by using the display2, for example. When the tractor setting (icon Ia3) is selected anddetermined with the first home screen S3, various setting items for thetractor 1 are displayed. The setting on the sprayer control mode iscalled therefrom. Thus, a control mode selection screen S7 asillustrated in FIG. 25 is displayed.

The control mode selection screen S7 displays two icons If1 and If2 onwhich the selectable control modes are described, and a green pointimage If3 is displayed on the icon of the set control mode in anoverlapping manner, so that the set control mode can be identified. Thecontrol mode selection screen S7 displays the icons 244, 254, 264, 274,and 284, corresponding to the command buttons 24 to 28, at the upperend.

On the control mode selection screen S7, the operator selects thedesired icon If1 or If2 by operating the encoder dial 22, and pressesthe enter button 23. Thus, the green point image If3 is displayed on theright side of the selected icon, and thus the control mode described onthe icon is set. FIG. 25 illustrates a state where the constant vehiclespeed control mode is set.

While the tractor 1 before starting the work is stopped, the operatorcan set the spraying amount, appropriate vehicle speed, and appropriatespraying pressure. The position of the transmission lever 172 (thetraveling vehicle speed information) can be checked on the sprayeroperation panel 178 while the tractor 1 is stopped, and thus thetraveling can be started after the position of the transmission lever172 is simply adjusted.

When a broadcaster is the currently interlocked working machine, thebroadcaster spraying start/stop function or the broadcaster sprayingamount adjustment function can be assigned to the working machinelifting/lowering switch 173 and the working machine lifting/loweringfine-control switches 174. The assignment is invalid when the workingmachine is not interlocked.

A function assigned to each switch can be set by the operator in advanceby using the display 2, for example. When the tractor setting (icon Ia3)is selected and determined on the first home screen S3, various tractorsetting items are displayed, and broadcaster switch assignment settingis called therefrom. Thus, a switch assignment screen S8 as illustratedin FIG. 26 is displayed.

On the switch assignment screen S8, two icons Ig1 and Ig2 on which namesof switches that can be assigned are displayed, and icons Ig3 and Ig4displayed on the right of the icons Ig1 and Ig2 and on which functionsassigned to the switches Ig1 and Ig2 are described are displayed. Theicons Ig3 and Ig4 are selectively displayed. The switch assignmentscreen S8 displays the icons 244, 254, 264, 274, and 284, correspondingto the command buttons 24 to 28, at the upper end.

While the switch assignment screen S8 is displayed, the operator selectsthe desired icon Ig3 or Ig4 by operating the encoder dial 22, andpresses the enter button 23. Thus, the display content of the selectedicon can be scrolled with the encoder dial 22. Then, the operatorselects a desired function by operating the encoder dial 22, and pressesthe enter button 23. Then, the selected function is assigned to theswitch described on the icon displayed on the left side.

As an example, in FIG. 26 , the broadcaster spraying start/stop isassigned to the working machine lifting/lowering switch 173. Morespecifically, the spraying starts when the working machinelifting/lowering switch 173 is slid upward, and stops when the switch isslid downward. The spraying amount adjustment is assigned to the workingmachine lifting/lowering fine-control switches 174. More specifically,the spraying amount is increased when the upper one of the workingmachine lifting/lowering fine-control switches 174 is pressed, and isdecreased when the lower one of the switches is pressed.

As described above, the desired functions for operating the currentlyinterlocked working machine are assigned to the switches (the workingmachine lifting/lowering switch 173 and the working machinelifting/lowering fine-control switches 174) provided to the transmissionlever 172. Thus, the operator can easily operate the assigned functionsat hand without releasing his or her hand from the transmission lever172 for operating the broadcaster controller, and thus can enjoy a lesscumbersome operation.

INDUSTRIAL APPLICABILITY

The present invention can be used for work vehicles such as a tractorfor farm work and a wheel loader for construction work.

REFERENCE SIGNS LIST

-   1 tractor (work vehicle)-   3 control device (control unit)-   21 liquid crystal panel (display unit)-   22 encoder dial (operation unit)-   23 enter button (operation unit)-   24 command button (operation unit)-   25 command button (operation unit)-   26 command button (operation unit)-   27 command button (operation unit)-   28 command button (operation unit)-   172 transmission lever-   173 working machine lifting/lowering switch (switch)-   174 working machine lifting/lowering fine-control switch (switch)

The invention claimed is:
 1. A tractor to which a working machine isattachable, the tractor comprising: an operation unit configured to becoupled and decoupled with the working machine, and to operate theworking machine while coupled to the working machine; and adetermination operation unit configured to switch the working machineinto an interlocked state with the tractor.
 2. The tractor according toclaim 1, further comprising a display unit configured to display anindication of a second working machine such that the indication isnon-selectable, wherein the working machine is attached to the tractorand the second working machine is detached from the tractor.
 3. Thetractor according to claim 1, further comprising: a control unit coupledto the operation unit and configured to receive an input from theoperation unit and, based on a determination by the determinationoperation unit that the working machine is in the interlocked state,initiate operation of the working machine based on the received input;and wherein, based on a sprayer being interlocked as the workingmachine, the operation unit is configured to operate a sprayer functionof the sprayer.
 4. The tractor according to claim 3, wherein: theoperation unit includes an operation tool; and based on the sprayerbeing interlocked as the working machine, the operation tool isconfigured to operate at least one of: a spraying start/end function ofthe sprayer, a spraying amount adjustment function of the sprayer, anextending/contracting adjustment function of a boom of the sprayer, aninclination adjustment function of the boom, an opening/closingadjustment function of the boom, and a lifting/lowering adjustmentfunction of the boom.
 5. The tractor according to claim 1, furthercomprising: a control unit coupled to the operation unit and configuredto, responsive to the operation unit, initiate operation of the workingmachine based on a determination by the determination operation unitthat the working machine is in an interlocked state; and wherein, basedon a broadcaster being interlocked as the working machine, the operationunit is configured to operate a broadcaster function of the broadcaster.6. The tractor according to claim 5, wherein: the operation unit of thetractor includes an operation tool; and based on the broadcaster beinginterlocked as the working machine, the operation tool is configured tooperate at least one of: a spraying start/end function of thebroadcaster, and a spraying amount adjustment function of thebroadcaster.
 7. The tractor according to claim 1, wherein: the operationunit is configured to be coupled to each working machine of a pluralityof working machines, the plurality of working machines including theworking machine and another working machine; based on the workingmachine being in an interlocked state, the operation unit is configuredto operate the working machine; and based on the other working machinebeing in an interlocked state, the operation unit is configured tooperate the other working machine.
 8. A work vehicle to which a workingmachine is attachable, the work vehicle comprising: a control deviceconfigured to: initiate, based on a first signal received from a firstinput device, a first operation configured to interlock a work vehicleand a working machine of at least two working machines; initiate, basedon the first signal received from the first input device, a secondoperation configured to couple a second input device with the workingmachine of the at least two working machines; and initiate, based on asecond signal received from the second input device, an operation of theworking machine of the at least two working machines determined to beinterlocked with the work vehicle.
 9. The work vehicle according toclaim 8, further comprising: the first input device, the first inputdevice including a screen configured to display, for each workingmachine of the at least two working machines, a correspondingindication; and the second input device, the second input deviceincluding a lever and configured to be operationally coupled andoperationally decoupled with the working machine of the at least twoworking machines and to operate the working machine of the at least twoworking machines while coupled to the working machine of the at leasttwo working machines.
 10. The work vehicle according to claim 8, whereinthe control device is further configured to receive the first signalfrom the first input device.
 11. The work vehicle according to claim 8,wherein the first input device is configured to receive a first inputand send the first signal to the control device based on receiving thefirst input.
 12. The work vehicle according to claim 8, wherein: theworking machine comprises at least three working machines; each of theat least three working machines is coupled to the work vehicle and ableto be interlocked; at least one of the at least three working machinesis coupled to a first end of the work vehicle; and at least one of theat least three working machines is coupled to a second end of the workvehicle, the second end different than the first end.
 13. The workvehicle according to claim 12, wherein the control device is furtherconfigured to determine of which working machine of the at least threeworking machines is interlocked with the work vehicle.
 14. The workvehicle according to claim 8, wherein the working machine of the atleast two working machines comprises a sprayer or a broadcaster.
 15. Amethod comprising: interlocking a work vehicle and a first workingmachine of at least two working machines based on a first signalreceived from a first input device; coupling a second input device andthe first working machine based on the first signal received from thefirst input device; and operating the first working machine determinedto be interlocked to the work vehicle based on a second signal receivedfrom the second input device.
 16. The method according to claim 15,wherein the first input device comprises a screen configured to display,for each working machine of the at least two working machines, acorresponding indicator.
 17. The method according to claim 16, whereinthe second input device comprises a lever and is configured to beoperationally coupled and operationally decoupled with the first workingmachine of the at least two working machined and to operate the firstworking machine of the at least two working machines while coupled tothe first working machine of the at least two working machines.
 18. Themethod according to claim 15, further comprising determining whichworking machine of the at least two working machines is interlocked withthe work vehicle.
 19. The method according to claim 15, furthercomprising: receiving a third signal from the first input device; basedon the received third signal: di-interlocking the first working machine;decoupling the second input device and the first working machine; or acombination thereof.
 20. The method according to claim 19, furthercomprising: interlocking the work vehicle and a second working machineof at least two working machines; coupling the second input device andthe second working machine; and operating the second working machinedetermined to be interlocked to the work vehicle based on the secondinput device.